A network may include the interconnection of multiple devices, such as personal electronic entertainment devices. In such a network, the interconnected devices may transfer and share data, including media data. In such a network, there may be data such as menus and other informational displays that is provided to one or more display devices in the network. In general, such data may be referred to as an on screen display (OSD). An OSD is an image that may be presented together with one or more other images on a screen. The OSD may or may not be transparent such that the OSD and another image can be simultaneously seen. The OSD may be purely informational (such as an OSD indicating the current channel of a television or a stock ticker) or may include a graphical user interface (GUI) that allows a user to select a feature through, for example, a remote control device. The OSD is often generated from a different source and is superimposed on another image such that a portion of the other image is partially or completely obscured while the OSD is displayed. For example, a television, DVD player, STB (set top box), or other device can generate information such as volume, channel, time information, or a menu in response to signals from a remote control device or the pressing of buttons on the television, set top box, DVD player, or other video source device. In addition to being used in TVs, OSDs have also been used in connection with computer displays. Some video equipment boxes may include more than one video source device. Some video devices are both video source devices and video display devices.
In conventional systems, the OSD signals can be generated inside control circuitry of the television or inside other devices such as a set top box or DVD (Digital Versatile Disc) player and be provided remotely from these devices to the television. For example, when a remote control device provides a channel change command to a television, control circuitry in the television may cause an OSD with the new channel to appear on the television screen. Alternatively, if the remote control device provides a channel change command to a set top box, the set top box may generate OSD signals and provide the OSD signals to the television to be displayed on the television screen.
FIG. 1 illustrates a conventional system that includes a video signal source 12 that provides compressed or uncompressed video to a set top box 16. Examples of the video source include a cable television outlet and a satellite television receiver. Examples of set top boxes include cable television boxes and satellite television boxes. Source 12 also may provide audio signals. Set top box 16 provides uncompressed analog video signals or uncompressed digital video signals to a display control circuitry 20 of a television 18. As an example, uncompressed digital video signals may be provided between set top box 16 and display control circuitry 20 of television 18 through a High Definition Multimedia Interface (HDMI). Display control circuitry 20 could receive video from other devices including a DVD player, DVR (digital video recorder), VCR (video cassette recording device), hand held video source device, or other device, in addition to or in replace of set top box 16.
The video signals are provided from display control circuitry 20 to display 30 to be displayed on screen 34. In the case in which OSDs are generated by set top box 16, the OSDs may be combined as part of the uncompressed video signals and sent to television 18 to be displayed. Display control circuitry 20 includes a frame buffer 24 to present OSD signals that are combined with the uncompressed video in blender circuitry 26. Blender circuitry 26 provides the combined signals to display 30 to be displayed on screen 34.
However, in practice, a network may include both newer and older devices, with the older devices not supporting all protocol requirements of the new system. Conventional devices may not support protocol requirements for OSD data and similar requirements. For this reason, there may be no interface for the input of the information display information to the older display devices, and thus the older devices in general may be unable to display such informational information.